Select2 Boxes is preventing modules/themes from altering attributes on auto-complete dropdowns

Problem/Motivation

The two auto complete methods in Select2BefFormStaticController currently define a new attributes array when the elements are configured to use select2. The issue I was running into is that I needed to add some css classes to one of my dropdowns, but because my module was loading before Select2 Boxes it was getting overwritten.

Proposed resolution

I put together a patch that changes the methods to set the attributes it's working with specifically and to add its css classes to the array instead of creating a new one.